How to Mix Bonsai Soil

Bonsai need a balanced soil mix for health.

Bonsai represents nature's grandeur in miniature. Historical evidence suggests people in China practiced the art of bonsai almost 2000 years ago. The trees, moss and miniature plants found in bonsai require specific care, including the correct soil mix. Soil that drains too quickly or retains too much moisture causes damage to the sensitive root system of the bonsai. Mixing your own bonsai soil ensures your small landscape has the nutrients, drainage and moisture retention needed for healthy and sustainable growth. Whether starting a new bonsai or transplanting older trees, making your own planting mix connects you to nature through an ancient art form.

1

Mix together two parts granite grit, one part loam and two parts peat moss for a basic soil mix. Alternately, for deciduous trees, mix one part coarse sand, one part loam and one part peat. Compost can replace loam and leaf mold or finely shredded bark can replace peat.

2

Stir the ingredients thoroughly in a container. Break up any clumps.

3

Sift the soil mixture through two screens to achieve a uniform texture. Use a one-sixteenth-inch screen to sift out dust particles. Follow with a one-quarter-inch screen to remove larger pieces.

4

Fertilize the bonsai approximately three weeks after new spring growth begins until the start of fall. Use a balanced granular fertilizer, such as a 20-20-20 blend, on top of the soil, re-applying when the granules dissolve. Switch to a 0-10-10 mixture in the fall and stop applying fertilizer in the winter. Fertilizing the soil is essential since the soil mix lacks essential minerals and nutrients for long term health.

Things You Will Need

Granite grit or coarse sand

Loam or compost

Peat moss or leaf mold

2 containers

1/16-inch screen

1/4-inch screen

Granular fertilizer

Tips

Window screens make economical choice for sifting bonsai soil.

Transplant bonsai in early spring when the new leaf buds first appear.

Bonsai soil drains quickly requiring you to water at least once a day during the growing season.

Bonsai typically need re-potted every 2 to 5 years depending on the age and plant species.

Warning

Peat moss can dry out and become hard if left too long without moisture, making it difficult for the soil mix to absorb water. It can also hold too much water, causing root rot. If you use peat moss, pay extra attention to the soil moisture levels.

About the Author

Kit Arbuckle is a freelance writer specializing in topics such as health, alternative medicine, beauty, senior care, pets and landscaping. She has training in landscaping and a certification in medicinal herbs from a botanical sanctuary.